Support munmap multiple single VMA chunks with remaining ranges

This commit is contained in:
Hui, Chunyang 2022-08-22 08:25:29 +00:00 committed by volcano
parent 5c10af738e
commit f87ee7c7a4
2 changed files with 69 additions and 40 deletions

@ -257,55 +257,37 @@ impl VMManager {
chunk.unwrap().clone()
};
// Case 1: the overlapping chunk IS NOT a super set of munmap range
if !chunk.range().is_superset_of(&munmap_range) {
// munmap range spans multiple chunks
let munmap_single_vma_chunks = {
let overlapping_chunks = {
let current = current!();
let mut process_mem_chunks = current.vm().mem_chunks().write().unwrap();
let munmap_single_vma_chunks = process_mem_chunks
.drain_filter(|p_chunk| {
p_chunk.is_single_vma() && p_chunk.range().overlap_with(&munmap_range)
})
.collect::<Vec<ChunkRef>>();
if munmap_single_vma_chunks
.iter()
.find(|chunk| !munmap_range.is_superset_of(chunk.range()))
.is_some()
{
// TODO: Support munmap multiple single VMA chunk with remaining ranges.
return_errno!(
EINVAL,
"munmap multiple chunks with remaining ranges is not supported"
);
}
// Munmap ranges in default chunks
for chunk in process_mem_chunks
let process_mem_chunks = current.vm().mem_chunks().read().unwrap();
process_mem_chunks
.iter()
.filter(|p_chunk| p_chunk.range().overlap_with(&munmap_range))
{
match chunk.internal() {
ChunkType::SingleVMA(_) => {
unreachable!() // single-vma chunks should be drained already
}
ChunkType::MultiVMA(manager) => manager
.lock()
.unwrap()
.chunk_manager_mut()
.munmap_range(munmap_range)?,
}
}
munmap_single_vma_chunks
.cloned()
.collect::<Vec<ChunkRef>>()
};
let mut internl_manager = self.internal();
munmap_single_vma_chunks.iter().for_each(|p_chunk| {
internl_manager.munmap_chunk(p_chunk, None);
});
for chunk in overlapping_chunks.iter() {
match chunk.internal() {
ChunkType::SingleVMA(_) => {
let mut internl_manager = self.internal();
internl_manager.munmap_chunk(chunk, Some(&munmap_range))?
}
ChunkType::MultiVMA(manager) => manager
.lock()
.unwrap()
.chunk_manager_mut()
.munmap_range(munmap_range)?,
}
}
return Ok(());
}
// Case 2: the overlapping chunk IS a super set of munmap range
debug_assert!(chunk.range().is_superset_of(&munmap_range));
match chunk.internal() {
ChunkType::MultiVMA(manager) => {
return manager
@ -696,7 +678,9 @@ impl InternalVMManager {
munmap_range.unwrap()
}
};
debug_assert!(chunk.range().is_superset_of(munmap_range));
// Either the munmap range is a subset of the chunk range or the munmap range is
// a superset of the chunk range. We can handle both cases.
let mut vma = vma.lock().unwrap();
debug_assert!(chunk.range() == vma.range());

@ -24,6 +24,7 @@
#define ALIGN_UP(x, a) ALIGN_DOWN((x+(a-1)), (a))
#define MAX_MMAP_USED_MEMORY (4 * MB)
#define DEFAULT_CHUNK_SIZE (32 * MB) // This is the default chunk size used in Occlum kernel.
// ============================================================================
// Helper functions
@ -676,6 +677,49 @@ int test_munmap_whose_range_intersects_with_multiple_mmap_regions() {
return 0;
}
int test_munmap_whose_range_intersects_with_several_chunks() {
int prot = PROT_READ | PROT_WRITE;
int flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED;
size_t len = 1 * MB;
// Allocate three continuous single vma chunks at the end of the default chunk
size_t hint_1 = HINT_BEGIN + DEFAULT_CHUNK_SIZE;
void *addr = mmap((void *)hint_1, len, prot, flags, -1, 0);
if ((size_t)addr != hint_1) {
THROW_ERROR("fixed mmap with good hint failed");
}
size_t hint_2 = hint_1 + len;
addr = mmap((void *)hint_2, len, prot, flags, -1, 0);
if ((size_t)addr != hint_2) {
THROW_ERROR("fixed mmap spans over two chunks failed");
}
size_t hint_3 = hint_2 + len;
addr = mmap((void *)hint_3, len, prot, flags, -1, 0);
if ((size_t)addr != hint_3) {
THROW_ERROR("fixed mmap spans over two chunks failed");
}
// Munmap the range spans above three ranges
size_t munmap_start = hint_1 + len / 2;
size_t munmap_end = hint_3 + len / 2;
if (munmap((void *)munmap_start, munmap_end - munmap_start) < 0) {
THROW_ERROR("munmap failed");
}
if (check_buf_is_munmapped((void *)munmap_start, munmap_end - munmap_start) < 0) {
THROW_ERROR("munmap does not really free the memory");
}
if (munmap((void *)hint_1, 3 * len) < 0) {
THROW_ERROR("munmap remaining ranges failed");
}
return 0;
}
int test_munmap_with_null_addr() {
// Set the address for munmap to NULL!
//
@ -1328,6 +1372,7 @@ static test_case_t test_cases[] = {
TEST_CASE(test_munmap_whose_range_intersects_with_a_mmap_region),
TEST_CASE(test_munmap_whose_range_intersects_with_no_mmap_regions),
TEST_CASE(test_munmap_whose_range_intersects_with_multiple_mmap_regions),
TEST_CASE(test_munmap_whose_range_intersects_with_several_chunks),
TEST_CASE(test_munmap_with_null_addr),
TEST_CASE(test_munmap_with_zero_len),
TEST_CASE(test_munmap_with_non_page_aligned_len),